U.S. patent application number 10/625079 was filed with the patent office on 2004-07-08 for percutaneous surgical instruments and methods using the same.
Invention is credited to Solomon, Stephen.
Application Number | 20040133195 10/625079 |
Document ID | / |
Family ID | 32684799 |
Filed Date | 2004-07-08 |
United States Patent
Application |
20040133195 |
Kind Code |
A1 |
Solomon, Stephen |
July 8, 2004 |
Percutaneous surgical instruments and methods using the same
Abstract
Method for ablating a tumor in a body while protecting a nearby
structure from the effects of the ablation in which an ablation
shield is interposed between the tumor and the nearby structure and
then one or more ablation sources of an ablation device is
activated to ablate the tumor while the nearby structure is
shielded by the ablation shield. Preferably, the ablation procedure
is performed while imaging at least a region including and
surrounding the tumor so that the ablation device can be guided
toward the tumor based on the imaging. The ablation shield can also
be guided percutaneously between the nearby structure and the tumor
based on the imaging. Additional surgical instruments for
percutaneous use and method for performing surgery using the same
are also disclosed.
Inventors: |
Solomon, Stephen;
(Baltimore, MD) |
Correspondence
Address: |
FRISHAUF, HOLTZ, GOODMAN & CHICK, PC
767 THIRD AVENUE
25TH FLOOR
NEW YORK
NY
10017-2023
US
|
Family ID: |
32684799 |
Appl. No.: |
10/625079 |
Filed: |
July 22, 2003 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
60397870 |
Oct 3, 2002 |
|
|
|
Current U.S.
Class: |
606/41 ;
606/49 |
Current CPC
Class: |
A61B 2090/0445 20160201;
A61B 10/0233 20130101; A61B 18/1477 20130101; A61B 90/04 20160201;
A61B 2018/00244 20130101; A61B 2018/1425 20130101 |
Class at
Publication: |
606/041 ;
606/049 |
International
Class: |
A61B 018/14 |
Claims
I claim:
1. A method for ablating or irradiating a tumor in a body while
protecting a nearby structure from the effects of the ablation,
comprising the steps of: inserting an ablation device to a location
in the body proximate the tumor, the ablation device having at
least one ablation source; interposing an ablation shield between
the tumor and the nearby structure; and then activating the
ablation source to ablate the tumor while the nearby structure is
shielded by the ablation shield.
2. The method of claim 1, further comprising the steps of: imaging
at least a region including and surrounding the tumor; and guiding
the ablation device toward the tumor based on the imaging.
3. The method of claim 1, wherein at least one ablation source is a
plurality of wires, the wires being activated to emit
radio-frequency current from their tips to create heat to ablate
the tumor.
4. The method of claim 1, wherein the ablation shield is interposed
percutaneously.
5. The method of claim 1, further comprising the steps of: imaging
at least a region including and surrounding the tumor and the
nearby structure; and guiding the ablation shield to a position
between the tumor and the nearby structure based on the
imaging.
6. The method of claim 1, further comprising the steps of: imaging
at least a region including and surrounding the tumor and the
nearby structure; guiding the ablation device toward the tumor
based on the imaging; and guiding the ablation shield to a position
between the tumor and the nearby structure based on the
imaging.
7. The method of claim 1, wherein the ablation shield is a
balloon.
8. The method of claim 7, further comprising the step of inflating
the balloon with a fluid after the balloon is interposed between
the tumor and the nearby structure and prior to activation of the
at least one ablation source.
9. The method of claim 8, further comprising the step of selecting
the fluid to inflate the balloon from a group consisting of air,
carbon dioxide and deionized water.
10. The method of claim 8, further comprising the step of selecting
the fluid based on the type of ablation source.
11. The method of claim 1, further comprising the step of
constructing the ablation shield to increase a distance between the
tumor and the nearby structure when interposed therebetween.
12. The method of claim 1, further comprising the step of
constructing the ablation shield from a material which serves as a
shielding material to counteract the effects of the at least one
ablation source.
13. The method of claim 1, wherein the ablation shield is a fan
retractor having an expandable fan portion folded upon
interposition of the fan retractor between the tumor and the nearby
structure, further comprising the step of expanding the fan portion
after the fan retractor is interposed between the tumor and the
nearby structure and prior to activation of the at least one
ablation source.
14. The method of claim 13, further comprising the step of
selecting the orientation of the fan retractor such that the fan
portion expands either to push the nearby structure away from the
tumor or to cause a substantial part of the fan portion to be
present between the tumor and the nearby structure.
15. The method of claim 13, wherein the fan portion expands to
causes a substantial part of the fan portion to be present between
the tumor and the nearby structure, further comprising the step of
selecting the material of the fan portion to counteract the effects
of the at least one ablation source.
16. A method for treating a tumor requiring multiple, sequential
treatment, comprising the steps of: performing a first treatment on
the tumor; marking the area of the tumor treated during the first
treatment; and performing at least one subsequent treatment on the
tumor based the marked area of the tumor.
17. The method of claim 16, wherein the treatments performed on the
tumor are radiofrequency ablations, the step of marking the area of
the tumor comprising the step of placing a radio-opaque material at
a location at ends of wires of a needle probe used in the
radiofrequency ablations.
18. A method for differentiating between instruments used in
surgery, comprising the steps of: providing a plurality of
instruments used for surgery with a different signature; and
enabling visibility of the signatures during imaging performed
during the surgery.
19. The method of claim 18, further comprising the step of
incorporating each instrument with the same signature in multiple
signature types such that the same signature is visible for imaging
for multiple modalities.
20. A method for biopsying an internal portion of the body,
comprising the steps of: inserting a biopsy needle into the body;
cutting the internal portion of the body with the biopsy needle;
positioning a tip of the biopsy needle near to the biopsy site;
grounding the body; and activating an electrical source to apply
electricity to at least a tip of the biopsy needle such that the
biopsy site is cauterized.
Description
CROSS REFERENCE TO RELATED APPLICATION
[0001] This application claims priority under 35 U.S.C.
.sctn.119(e) of U.S. provisional patent application Ser. No.
60/397,870 filed Jul. 22, 2002.
FIELD OF THE INVENTION
[0002] The present invention relates generally to percutaneous
surgical instruments and more particularly to surgical instruments
which prevent damage to an organ or tissue in a body during
ablation or radiation of a nearby tumor.
[0003] The present invention also relates generally to a method and
apparatus for identifying tools and instruments used during surgery
which is imaged and more particularly to a method and apparatus for
enabling the identification of different tools used during a
surgery in which multiple tools are placed in the body
simultaneously.
[0004] The present invention also relates to a method and apparatus
for enabling electrocautery percutaneously.
[0005] The present invention further relates to a method for
marking or labeling a treatment zone after percutaneous ablation of
a tumor or a similar surgical procedure.
[0006] The present invention also relates to a method and apparatus
for performing an appendectomy or similar surgical procedure in
which a single device is capable of performing the required
surgical steps.
BACKGROUND OF THE INVENTION
[0007] Advances in imaging have allowed many surgical procedures to
become percutaneous ones, i.e., able to be perform through the
skin. Incisions in surgery are performed in order to allow
visualization of structures via cameras and other optical imaging
devices. Although laparoscopic surgery requires insufflation in
order to enable visualization, advances in imaging technology with
CT, MR, ultrasound, nuclear medicine and x-rays allow a physician
to "see" through the skin to perform surgical procedures without
having to make incisions in the skin. The elimination of incisions
in the skin for at least some surgical procedures reduces the
recuperation time and the risk of possible infections.
[0008] One common procedure performed percutaneously which utilizes
imaging, rather than surgical incision and direct visualization, is
the ablation of tumors with percutaneous needle devices. The
imaging system guides the placement of the percutaneous needle
device into the tumor for ablation. Such procedures are being used
more commonly today and their use is expected to increase.
[0009] The most common of the percutaneous needle devices relies on
radiofrequency energy, but microwave, laser, ultrasound,
cryotherapy, and interstitial irradiation are similar means for
performing tumor ablation. Radiofrequency ablation is used for
treating localized cancer tumors that cannot be removed surgically,
such as liver tumors. Liver tumors are usually located deep inside
the body where surgeons cannot reach with their hands easily.
[0010] In a common radiofrequency ablation procedure, the first
step is to place a needle with a plastic insulated shaft into the
tumor with imaging guidance. Then, the surgeon presses a button on
the needle probe and wires similar to the backbone of an umbrella
shoot out and cover a portion or all of the tumor. Once the patient
is connected to ground, alternating radiofrequency current from the
wire tips then agitate ions in the tissue surrounding the needle,
creating frictional heat to heat the tumor. The radiofrequency
current thus serves as an ablation source for enabling ablation of
the tumor.
[0011] A few clinical examples of radiofrequency ablation of tumors
include radiofrequency ablation of renal tumors (see Su L M,
Jarrett T. W., Chan D. Y., Kavoussi L. R., Solomon S. B.,
Percutaneous computed tomography-guided radiofrequency ablation of
renal masses in high surgical risk patients: preliminary results.
Urology 2003 April; 61(4 Supplement 1):26-33), laser ablation of
liver tumors (see Dick E. A., Joarder R, de Jode M, Taylor-Robinson
S. D., Thomas H. C., Foster G. R., Gedroyc W. M., MR-guided laser
thermal ablation of primary and secondary liver tumours. Clin.
Radiology 2003 February; 58(2):112-20, and Erce C, Parks R. W.,
Interstitial ablative techniques for hepatic tumours. Br J Surg
2003 March; 90(3):272-89), and radiofrequency ablation of adrenal
tumors (see Wood B. J., Abraham J, Hvizda J. L., Alexander H. R.,
Fojo T., Radiofrequency ablation of adrenal tumors and
adrenocortical carcinoma metastases. Cancer 2003 February
1;97(3):554-60).
[0012] One of the major limitations to this type of tumor ablation
procedure is the lack of tools to optimize these procedures. For
example, when critical healthy, normal structures, such as organs
and tissue, are near targeted cancerous structures, the critical
ones are liable to be inadvertently, detrimentally affected and
damaged by the thermal or radiation heat being released by the
ablation needle probe and applied to the target structures. It
would be desirable to move these critical normal organs and tissue
away from the targeted cancerous structures because it has been
documented that complications to normal tissue may occur when
ablating a nearby tumor (see Chopra S, Dodd G. D. 3rd, Chanin M.
P., Chintapalli K N., Radiofrequency ablation of hepatic tumors
adjacent to the gallbladder: feasibility and safety. AJR Am J
Roentgenol 2003 March; 180(3):697-701). For example, in placing a
percutaneous needle, a loop of bowel might be retracted away from
the site of the needle tip. Another example would be when applying
energy for thermal ablation or interstitial radiation, one might
want to separate normal tissue from the ablation source. Ideally,
there would be thermal or radiation protection devices that could
shield the normal tissue or structures from the deadly thermal or
radiation energy applied.
[0013] In a separate but related field, when a biopsy is performed,
a portion of a structure is removed possibly causing bleeding from
a remaining part of the structure. There is not believed to be a
tool which can be guided by images to stop bleeding
percutaneously.
[0014] In laparoscopic surgery, incisions are smaller because
visualization is performed through small cameras or other imaging
devices. While these cameras provided remote visualization, they
required a new set of tools to enable the procedures (see Seifman
B. D., Wolf J. S. Jr., Technical advances in laparoscopy: hand
assistance, retractors, and the pneumodissector. J, Endourol. 2000
Dec. 14(10):921-8). Retractors and cautery devices are examples of
devices that had to be specifically made for this new type of
surgery.
OBJECTS AND SUMMARY OF THE INVENTION
[0015] It is an object of the present invention to provide a new
method for ablating tumors while shielding surrounding normal
structures, such as tissue and organs.
[0016] It is another object of the present invention to provide new
apparatus for placement between a cancerous structure and
surrounding normal structures to shield the normal structures from
the application of treatment to the cancerous structure, such as
the application of heat, cold, radiation and ultrasound, and
methods for using the same.
[0017] It is another object of the present invention to provide new
tools for distancing healthy tissue and organs from a cancerous
tumor being treated by ablation, in particular tools capable of
being used percutaneously and guided by imaging techniques to
positions between the tumor and the healthy tissue and organs, and
methods for using the same.
[0018] It is yet another object of the present invention to provide
a method and apparatus for identifying tools and instruments used
during surgery which is imaged and more particularly to a method
and apparatus for enabling the identification of different tools
used during a surgery in which multiple tools are placed in the
body simultaneously.
[0019] Another object of the present invention is to provide a new
method and apparatus for enabling electrocautery
percutaneously.
[0020] Yet another object of the present invention is to provide a
new method and apparatus for marking or labeling a treatment zone
after percutaneous ablation of a tumor or a similar surgical
procedure.
[0021] Still another object of the present invention also relates
to a new method and apparatus for performing an appendectomy or
similar surgical procedure in which a single device is capable of
performing the required surgical steps.
[0022] In order to achieve at least some of the objects, a method
for ablating a tumor in a body while protecting a nearby structure
from the effects of the ablation comprises the steps of inserting
an ablation device to a location in the body proximate the tumor,
interposing an ablation shield between the tumor and the nearby
critical structure and then activating one or more ablation sources
of the ablation device to ablate the tumor while the nearby
structure is shielded by the ablation shield. Preferably, the
ablation procedure is performed while imaging at least a region
including and surrounding the tumor so that the ablation device can
be guided toward the tumor based on the imaging. The ablation
shield can also be guided percutaneously between the nearby
structure and the tumor based on the imaging.
[0023] If the ablation is a radiofrequency ablation, then the
ablation sources are a plurality of wires which are activated to
emit radio-frequency current from their tips to create heat to
ablate the tumor.
[0024] In one embodiment, the ablation shield is an at least
partially inflatable balloon which may be inflated with a fluid
after the balloon is interposed between the tumor and the nearby
structure and prior to activation of the ablation source(s).
Inflation of the balloon causes an increase in the distance between
the tumor and the nearby structure and also forms a barrier which
may be designed to prevent the transmission of heat generated by
the radiofrequency current to the nearby structure. In the latter
case, it would be beneficial to form the balloon from a shielding
material which counteracts the effects of the radiofrequency
current, i.e., as a heat shield which could be made from a
heat-absorbing material.
[0025] In another embodiment, the ablation shield is a fan
retractor having an expandable fan portion folded upon
interposition of the fan retractor between the tumor and the nearby
structure. The fan portion is expanded after the fan retractor is
interposed between the tumor and the nearby structure and prior to
activation of the ablation source(s). The orientation of the fan
retractor can be selected such that the fan portion expands either
to push the nearby structure away from the tumor (in which case the
distance between the nearby structure and tumor reduces the impact
of the ablation source(s) on the nearby structure) or to cause a
substantial part of the fan portion to be present between the tumor
and the nearby structure (in which case, the fan material acts as a
shield to reduce the impact of the ablation source(s) on the nearby
structure). The fan may be partially composed of an x-ray
attenuating material that would shield from radiation. This may be
appropriate in brachytherapy applications in the breast or prostate
for example.
[0026] A method for treating a tumor requiring multiple, sequential
treatment which may use the ablation shield described above
comprising the steps of performing a first treatment on the tumor
(interposing the ablation shield between the tumor and the nearby
structures if desired), marking the area of the tumor treated
during the first treatment and performing at least one subsequent
treatment on the tumor based the marked area of the tumor. If the
treatments are radiofrequency ablations, marking the area of the
tumor may entail placing a radio-opaque material at a location at
ends of wires of a needle probe used in the radiofrequency
ablations.
[0027] A method for differentiating between instruments used in
surgery in accordance with the invention comprises the step of
providing a plurality of instruments used for surgery with a
different signature and enabling visibility of the signatures
during imaging performed during the surgery. To this end, each
instrument may incorporate with the same signature in multiple
signature types such that the same signature is visible for imaging
for multiple modalities.
BRIEF DESCRIPTION OF THE DRAWINGS
[0028] The invention, together with further objects and advantages
hereof, may best be understood by reference to the following
description taken in conjunction with the accompanying drawings,
wherein like reference numerals identify like elements and
wherein:
[0029] FIG. 1 is a schematic view showing placement of a first
embodiment of a shield between a tumor on a liver being treated and
a portion of a normal intestine for use in a method in accordance
with the invention.
[0030] FIG. 2 is a front view of a second embodiment of a shield in
accordance with the invention.
[0031] FIG. 3 is a front view of the shield shown in FIG. 2 in a
position during use in a method in accordance with the
invention.
[0032] FIG. 4A is a front view of the shield shown in FIG. 2 in a
position during a first manner of use in which a material is
interposed between a tumor and healthy, nearby structure in a
method in accordance with the invention.
[0033] FIG. 4B is a front view of the shield shown in FIG. 2 in a
position during a second manner of use in which it pushes healthy
structure away from a tumor being treated in a method in accordance
with the invention.
[0034] FIG. 5 is a view of a tumor being treated.
[0035] FIG. 6 is a view showing the application of a marking agent
to indicate a treated portion of the tumor.
[0036] FIG. 7 is a view showing the tumor of FIG. 5 after multiple
applications of a marking agent.
[0037] FIG. 8 is a view of a first instrument with a signature in
accordance with the invention when viewed on a screen of an imaging
device.
[0038] FIG. 9 is a view of a second instrument with a signature in
accordance with the invention when viewed on a screen of an imaging
device.
[0039] FIG. 10 shows a biopsy needle used for percutaneous
electrocautery.
[0040] FIG. 11 shows an instrument for use in appendectomies in
accordance with the invention.
[0041] FIG. 12 shows the instrument of FIG. 11 in use for an
appendectomy.
[0042] FIGS. 13 and 14 show a side view of the operative use of the
instrument in FIG. 11.
[0043] FIG. 15 shows a view of the removal of the cut portion of
the appendix.
[0044] FIG. 16 shows a resector and/or morcellator in accordance
with the invention.
[0045] FIGS. 17 and 18 show operative positions of use of the
resector and/or morcellator shown in FIG. 16.
DETAILED DESCRIPTION OF THE INVENTION
[0046] Described below are several innovations for performing
surgery and more particularly for performing percutaneous surgery
in conjunction with imaging of the surgical area. Each of these
innovations can be used independently of one another or in
combination with one another.
[0047] Referring first to FIG. 1, a method for ablating a tumor
will be described in connection with several embodiments of an
apparatus in accordance with the invention in which the ablation
source used to ablate the tumor is a plurality of radiofrequency
current-generating sources. It should be understood that other
ablation and radiation sources can also be used in the
invention.
[0048] As shown in FIG. 1, it is desired to ablate a tumor 12 on a
liver 10, for example. To this end, a needle probe 14 with a
plastic insulated shaft is inserted into the tumor 12, preferably
percutaneously with imaging guidance. When the surgeon presses a
button on the needle probe 14, wires 16 similar to the backbone of
an umbrella shoot out and cover a portion or all of the tumor 12.
The wires 16 are then activated so that alternating radio-frequency
current is generated at the tips of the wires 14 and agitates ions
in the tissue surrounding the needle probe 14, creating frictional
heat to heat the tumor 12.
[0049] Prior to the activation of the wires 16, it is determined
whether there is/are tissue or organs (represented by a portion of
the intestines 18) proximate to the tumor 12 which would be
adversely affected by the heat created by the radio-frequency
current applied to the wires 16 and thus should be protected
therefrom. If so, an ablation shield 20 is interposed
percutaneously between the tumor 12 and the intestines 20 to
prevent the transmission of heat from the tips of the wires 14 to
the intestines 18.
[0050] The ablation shield 20 may take various forms. In the form
illustrated in FIG. 1, the ablation shield 20 is a balloon catheter
22, at least an interior portion 24 of which is inflatable with a
fluid. The balloon catheter 22 usually enters the body in a
non-inflated state and is guided, using imaging techniques, between
the tumor 12 and the intestines 18 and then a fluid is directed
into the interior portion 24.
[0051] The fluid may be a gas, such as air and carbon dioxide, or a
non-conducting liquid such as deionized water. The fluid used
depends in part on the effect being applied to the tumor 12, with
the fluid preferably being one which is designed to counter or
prevent the transmission of the effect being applied to the tumor
12. For example, for radiofrequency ablation, the effect is one of
heat so that the fluid in the balloon catheter 22 would preferably
be one which prevents the transmission of heat therethrough. If the
effect is ultrasound, i.e., an ultrasonic procedure is being
applied to ablate the tumor 12, then the fluid should preferably be
a material which impedes the transmission of ultrasonic energy.
Thus, the fluid may be selected based on the type of ablation
source, e.g., radiofrequency energy, ultrasonic energy, etc.
[0052] In addition to containing a substance that counters the
effect being applied to the tumor 12, the balloon catheter 22 also
serves to increase the distance between the tumor 12 and the
intestines 18. This is highly advantageous for treatments which
have a reduced effect over distance. For example, heat dissipates
in a direction away from the source so that by increasing the
distance between the heat source (the tips of the wires 16) and the
intestines 18, the effect of the heat is reduced irrespective of
the presence of any fluid in the balloon catheter 22. In this
regard, the balloon catheter 22 can be inflated to have various
diameters and thereby enable a variation in the extent to which the
intestines 18 are separated from the tumor 12.
[0053] Moreover, various sizes of balloon catheters 22 may be used,
e.g., an 8 mm balloon and a 22 mm balloon. The larger balloon can
contain more fluid than the smaller balloon and have a larger
inflatable interior enabling a larger separation between the tumor
12 and the intestines 18 than the smaller balloon. Indeed, it has
been found that the larger balloon results in a greater temperature
reduction between a tumor 12 and the intestines 18 than the smaller
balloon.
[0054] Furthermore, the balloon catheter 22 may be formed from a
material which serves as a shielding material to protect from
ablation sources. For radiofrequency ablation, the material of the
balloon catheter 22 would be non-absorbent of radiofrequency
energy, In the case of thermal ablation, the balloon 22 may include
or be made of a material that would have a protective heat
capacity. In the case of radiation protection, the balloon may
include or be made of lead. These radioactive shields may also be
placed prior to external radiation treatment.
[0055] An added feature of the balloon catheter 22 would be to make
the material of the balloon catheter 22 of a firm plastic material
or non-puncturable material so that it would resist bursting if a
needle probe accidentally contacted it.
[0056] After the radio-frequency energy is applied to the wires 16
and the ablation is complete, the balloon catheter 22 is deflated
and withdrawn from the body and the needle probe 14 is also
withdrawn.
[0057] An alternative ablation shield 20 is a fan retractor 26 as
shown in FIGS. 2 and 3. The fan retractor 26 has a body having a
head 28 and a shaft 30 and is inserted percutaneously into the body
shaft first. The shaft 30 includes an expandable fan portion 32
which is folded upon interposition of the fan retractor 26 between
the tumor 12 and the nearby intestines 18 (see FIG. 2). Once the
fan retractor 26 is positioned between the tumor 12 and the nearby
intestines 18, a button 34 on the head 28 is pressed releasing the
hold on the fan portion 32 and causing the fan portion 32 to expand
(see FIG. 3). The mechanism causing the hold on the fan portion 32
until pressing of the button 34 would be readily constructable by
one skilled in the art and would include a coupling 36 as shown in
dotted lines in FIGS. 2 and 3 which converts the downward pressure
on the button 34 into a movement releasing the restraint on the fan
portion 32.
[0058] Expansion of the fan portion 32 causes either the
interposition of a substantial portion of the fan portion 32
between the tumor 12 and the intestines 18 when the fan portion 32
expands at an angle to a plane defined by the tumor 12 and the
intestines 18 (FIG. 4A) or a forced separation of the intestines 18
away from the tumor 12 when the fan portion 32 expands against the
intestines 18 in the plane defined by the tumor 12 and the
intestines 18 (see FIG. 4B). Thus, the retractor fan 26 can be
oriented to either provide a physical shield between the tumor 12
and the intestines 18 (FIG. 4A) or separation between the
intestines 18 and the tumor 12 (FIG. 4B). The use of the fan
retractor 26 may depend on the type of ablation.
[0059] Note that the distance between the intestines 18 and the
tumor 12 (D1) is greater in FIG. 4A when the retractor fan 26 is
used to separate the intestines 18 from the tumor 12 than the
distance (D2) as shown in FIG. 4B when the retractor fan 26 is used
as a shield between the intestines 18 and the tumor 12. Separation
of the intestines 18 from the tumor 12 (FIG. 4A) reduces the effect
of the ablation source when the effect decreases with distance,
such as heat.
[0060] When used as a shield (FIG. 4B), the material of the fan
portion 32 of the retractor fan 26 can be selected to counteract
the effects of the ablation source, e.g., the tips of the wires 16
which emit radiofrequency energy. For example, in the case of
thermal ablation, the fan portion 32 may include or be made of a
material that would have a protective heat capacity. In the case of
radiation ablation, the fan portion 32 may be made of a material
such as lead or include lead. In the case of microwave energy used
for ablation, the fan portion 32 may be made of an electromagnetic
shielding material.
[0061] Referring now to FIGS. 5-7, an issue in the percutaneous
thermal ablation of the tumor may arise if the tumor 40 is larger
than the effective area of the ablation source. In this case,
multiple ablations must be performed, each effective on a portion
of the tumor 40. The combined effect of the multiple ablations will
hopefully encompass the entire tumor 40. However, for a subsequent
ablation of a portion of the tumor 40, it is not easy to ascertain
which portion of the tumor 40 has already been ablated. This issue
also arises for interstitial radiation procedures.
[0062] To facilitate identification of a portion of a tumor 40
which has already been ablated so that a subsequent ablation can be
performed on a non-ablated portion of the tumor 40, possibly with a
slight overlap with the ablated portion, the present invention
includes a marking or labeling system in which after ablation of a
portion of the tumor 40, that portion is marked. In this manner, in
spite of the performance of multiple ablations, there is no gap
between treatment zones.
[0063] As shown in FIG. 5, the tumor 40 is larger than the
effective area of the ablation source, i.e., the radiofrequency
current generated by the tips of wires 44 from the needle probe 42.
Thus, a first ablation is performed in which the left side of the
tumor 40 is ablated (portion 40a). After the radiofrequency current
is stopped, a marker 46 is released at the locations of the tips of
the wires 44 (see FIG. 6). The markers 46 may be a radio-opaque
glue material such as a mixture of methylmethacrylate and lipiodol
that is released through the ablation needle tines. The markers 46
may alternatively be released from a separate surgical instrument
inserted percutaneously into the body, i.e., a needle or the like.
That is, while imaging the area of the tumor 40, a needle filled
with a marking agent can be introduced into the body and pressed to
release a drop of marking agent at the locations of the tips of the
wires 44.
[0064] The marking agent should be visible to the imaging
procedure. Thus, a magnetic imaging procedure would be used in
conjunction with a magnetic material such as a metal fragment or
staple or a vitamin E containing mixture. An x-ray imaging
procedure would be used in conjunction with a radio-opaque
material, such as a barium or iodinated dye or glue.
[0065] The needle probe 42 is then removed and re-positioned to
ablate the non-ablated portion of the tumor 40 (portion 40b).
Ablation is performed and then the marking agent is again placed at
the location of the tips of the wires 44 of the needle probe 42
(FIG. 7). The image of the tumor 40 is then viewed to confirm that
the entire tumor 40 is ablated by the two ablation procedures.
[0066] By marking or labeling the ablated portion of a tumor, it is
easy to identify the non-ablated portion of the tumor and thereby
facilitate placement of the needle probe using imaging.
[0067] Referring now to FIGS. 8 and 9, it is often necessary and
desirable to know the position of specific instruments in a body
during surgery when multiple instructions are being used. Although
the identity of the instruments is readily ascertainable when the
instruments are outside of the body, when inside the body, it is
sometimes difficult to tell which instrument is which.
[0068] To facilitate identification of instruments when used during
surgery in which the surgical area is being imaged, the present
invention provides for the incorporation of an imaging signature
into surgical instruments so that when imaged, each instrument
provides a signature which indicates the type and identity of the
instrument. Each different instrument has a unique signature.
[0069] The "imaging signature" may be different depending on the
imaging modality being used (e.g., ultrasound, CT, MR, PET).
Multiple signature types may be applied to an instrument so that
the instrument may keep its signature regardless of the imaging
modality being used.
[0070] In one embodiment, an x-ray or CT imaging signature may be
accomplished by incorporating material of reduced radiodensity
within the shaft 50 of the instrument 48. As shown in FIGS. 8 and
9, the material of reduced radiodensity at locations 52 and 54.
This would create a "dashed" appearance. The instrument shown in
FIG. 8 has two dashed areas 52,54 and thus would be known to the
surgeon as being different from the instrument shown in FIG. 9. Of
course, the surgeon has to known the signature of the instruments
along with the identification of the instrument, i.e., he or she
has to known that two dashed areas 52,54 exemplifies a thin needle
probe (FIG. 8) where a single dashed area 52 exemplifies a thick
needle probe (FIG. 9).
[0071] Other means might be creating different thicknesses of
radiodense material. In ultrasound, the signatures would be
material with different echogenicities.
[0072] Referring now to FIG. 10, one of the concerns of performing
"surgery" percutaneously is control of bleeding. Electrocautery is
used in surgery to coagulate blood and stop bleeding.
Electrocautery can be incorporated into percutaneous tools such as
biopsy needles and ablation tools.
[0073] FIG. 10 shows a biopsy needle 60 connected to an electrical
source 62. A grounding pad 64 is also provided to attach to the
patient to ground them and prevent electrical shock. In use, the
biopsy needle 60 is inserted into the body to cut a portion of the
body for analysis external to the body. After the portion of the
body is cut, the part of the body from which the portion was cut
may bleed. To cauterize this portion, the tip 66 of the biopsy
needle 60 may be placed close to the bleeding site and the
electrical source 62 activated. The activation of the electrical
source 62 may be performed immediately after the cut portion is
received by the biopsy needle 60. It is important not to heat the
specimen such that it becomes uninterpretable.
[0074] By coupling a cauterization function to a biopsy needle (or
to an ablation tool which would be the same manner), an efficient
and safe percutaneous electrocautery can be achieved.
[0075] The biopsy needle 60 may be provided with an imaging
signature as discussed above with reference to FIGS. 8 and 9.
[0076] Referring now to FIGS. 11-15, in order to perform an
appendectomy percutaneously, an instrument 70 in accordance with
the invention is provided with two prongs 72, 74 at a proximal end
defining a jaw 76 which surrounds the cutting site 78 of the target
appendix 80. The instrument 70 is inserted percutaneously into the
body and manipulated to cause two portions of the appendix 80 to be
grasped, one by each prong 72, 74 (as shown in FIG. 13).
Thereafter, the appendix 80 is cut at the cutting site 78 (FIG.
14). The cut portion of the appendix 80a may be removed when one
prong 74 is opened (see FIG. 15).
[0077] The construction of the instrument 70 with two adjustable
prongs 72,74, independently adjustable by manipulation of a
component at the distal end, can be readily obtained by one skilled
in the art without undue experimentation.
[0078] The instrument 70 may be provided with an imaging signature
as discussed above with reference to FIGS. 8 and 9.
[0079] Referring now to FIGS. 16-18, a percutaneous resector and/or
morcellator 84 is shown for use when tissue needs to be removed
from the body. The resector 84 includes a wire 86 with a neck such
as a butterfly neck. The resector 84 is manipulated such that the
wire 86 surrounds or circumscribes the portion of the body to be
excised (FIG. 17). The wire 86 is then heated to cause the portion
to be excise and cut the tissue in a loop. The resector 84 also
includes a net 88 which captures the excised portion of the body
(FIG. 18).
[0080] The resector 84 may be provided with an imaging signature as
discussed above with reference to FIGS. 8 and 9.
[0081] While particular embodiments of the invention have been
shown and described, it will be obvious to those skilled in the art
that changes and modifications may be made without departing from
the invention in its broader aspects, and therefore, the aim in the
appended claims is to cover all such changes and modifications as
fall within the true spirit and scope of the invention.
* * * * *